We use symbolic model checking to verify a VHDL design. This paper mainly focuses on Computational Tree Logic (CTL) for model checking problem. We have explained these two terms “CTL” and “model checking” for providing a clear idea about these two. Most importantly we have explored the ways of uses of CTL formulae in the case of model checking. The importance of the model checking, the ways of ...

CTL escape mutations have been identified in several chronic infections, including mice infected with mouse hepatitis virus strain JHM. One outstanding question in understanding CTL escape is whether a CD8 T cell response to two or more immunodominant CTL epitopes would prevent CTL escape. Although CTL escape at multiple epitopes seems intuitively unlikely, CTL escape at multiple CD8 T cell epi...

There is good evidence that cytolytic T lymphocytes (CTL) 1 are derived from cytotytically inactive precursors (CTL-P). In most experimental systems for the activation of the precursors to CTL, extensive proliferation of the CTL-P is induced. Tbis proliferation depends on T cell growth factor (TCGF or interleukin 2), which acts only on T cells that have become TCGF responsive as a result of the...

A modular formalization of the branching time temporal logic CTL∗ is presented. Our formalization subsumes prior formalizations of propositional linear temporal logic (PTL) and computation tree logic (CTL). Moreover, the modularity allows to instantiate our formalization for different formal security models. Validity of axioms and soundness of inference rules in axiomatizations of PTL, UB, CTL,...

We show that the satisfiability problem for CTL, the branching time logic that allows boolean combinations of path formulas inside a path quantifier but no nesting of them, is 2-EXPTIME-hard. The construction is inspired by Vardi and Stockmeyer’s 2-EXPTIME-hardness proof of CTL∗’s satisfiability problem. As a consequence, there is no subexponential reduction from CTL to CTL which preserves sati...

A multi-valued version of CTL (mv-CTL), where both the propositions and the accessibility relation are multi-valued taking values in a nite quasi-boolean algebra, is considered. A general translation from mv-CTL to CTL model checking is deened. An application of the translation is shown for the most commonly used quasi-boolean algebras.

The involvement of the lymphocyte function-associated antigen-1 (LFA-1) membrane molecule in cytolytic T lymphocyte (CTL) interactions with lymphoid target cells was investigated using CTL clones derived from two patients with a heritable deficiency of LFA-1. LFA-1 surface expression on the CTL clones was 1% of the normal level of LFA-1, unchanged with prolonged culture, and identical on 14 dif...

The aim of this study was to determine the number and state of activity of cytolytic T lymphocytes (CTL) and their precursors (CTL-P) present in vivo during the early stages of viral infection. The local response to lethal infection with rabies virus was used as a model system that is not accessible to analysis by secondary activation in vitro. The local response to alloantigen served as a cont...

Compelling evidence now suggests that alphabeta CD8 cytotoxic T lymphocytes (CTL) have an important role in preventing human immunodeficiency virus (HIV) infection and/or slowing progression to AIDS. Here, we describe an HIV type 1 CTL polyepitope, or polytope, vaccine comprising seven contiguous minimal HLA A2-restricted CD8 CTL epitopes conjoined in a single artificial construct. Epitope-spec...

Simian virus 40 large tumor (T) antigen contains three H-2Db-restricted (I, II/III, and V) and one H-2Kb-restricted (IV) cytotoxic T lymphocyte (CTL) epitopes. We demonstrate that a hierarchy exists among these CTL epitopes, since vigorous CTL responses against epitopes I, II/III, and IV are detected following immunization of H-2b mice with syngeneic, T-antigen-expressing cells. By contrast, a ...